The present invention relates to a glow-discharge lamp made of insulated material provided with at least one gas supply means and evacuation openings means; an anode in said chamber body; a gas inner chamber which expands toward the anode and which is defined by sides of inner walls of the chamber body and whose diameter is largest at approximately the level of the anode and whose smallest diameter corresponds to an examination sector of the sample to be examined; a cathode adjacent one end of the chamber body; a sample placed at the cathode end of the chamber body and an end section in the form of a window means arranged at one end of the chamber body and wherein the glow-discharge lamp is used for atom absorption spectroscopy (AAS), optical emission spectroscopy processes (OES), atom fluoresence spectroscopy (AFS) and optogalvanic process (LEI).